(1) Field of the Invention
The invention concerns a rotary pump with a pump housing, consisting of plastic material that can be processed by injection molding, with a first housing part delimiting a pump space, which is connected to a second intermediate housing part accommodating an electric motor, comprising a split core and consisting of plastic material, a wound claw pole stator of the electric motor being mounted on the split core and a permanent magnetic rotor being mounted to rotate within split core, and a motor housing part, consisting of plastic material that delimits a motor space.
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
A generic rotary pump is known from US 2007/0290568 A1. During joining of a slotted return with the claw pole stator, a deformation process of a tab is carried out in the known rotary pump, through which a slit in the return ring is narrowed and the return therefore lies tightly against the claw pole stator. However, it has turned out that this connection, because of the low rigidity of the tab, cannot guarantee complete freedom from play in each case over the entire lifetime and under a variety of temperature conditions. Under these circumstances, unpleasant noise, vibrations and possibly even resonances can occur.